A survival game with real electricity — and a radio that reaches the Moon

Is there a survival game with real electricity?

In Openworld, electricity is built in. It's a voxel sandbox on a whole, round planet — walk straight and you come back to where you started — under a real sky with Moon phases and eclipses, and it runs natively on Mac, Windows and Linux. In that world, power is a resource like iron or wood: you produce it, you carry it, you store it, you spend it.

The rule that holds everything together: energy is conserved. A lamp draws a few dozen watts, a motor much more, the Furnace or a gas plant several kilowatts. Nothing runs on thin air, and that's exactly what makes it fun — a well-sized power plant is something you're proud of.

• 3sources: fuel, sunlight, batteries
• 3kinds of cable: signal, small and large power
• 256radio channels
• 0mods needed

Producing power: generators, solar panels, batteries

The generator

Your first plant. It burns any fuel — coal, charcoal, wood, or the oil and kerosene of its tank — turns a dynamo and gives up to 5 kW to its cables. Clever detail: it only burns for what your cables take. Light one lamp, it sips; start the Furnace, it works hard and your coal goes faster. Where that coal and oil come from is in our guide to factories and automation.

The solar panel

Glass over silicon cells on iron sheets, up to 400 W under the open sky. It gives the most when the Sun is high, less in the morning and evening, nothing at night. Clouds and rain cut it down, a roof over it leaves only a little diffuse light… and since Openworld's sky is real, a solar eclipse dims your panels too. Read about the eclipses you'll see in the game — and plan a battery.

The lithium battery

It stores 10 kWh of what your cables bring and gives it back, up to 5 kW, when the sky goes dark. A few panels on the roof and one battery are enough to keep a house lit all night. You make it from lithium ingots: lithium ore from the salt flats, smelted in the Furnace — which itself needs power. Everything links up.

Cables, consumption and overloads

Cables come in kinds: a thin signal cable that only carries a signal (up to 256 m), a small power cable (10 kW) and a large power cable (250 kW), all made at the metal mill. A bigger cable carries more watts — volts times amps, like the real thing. Ask too much of a cable and it trips for a few seconds: what's behind it goes dark. To carry a big plant's power far away, a transformer joins small and large cables (97 % efficient): it steps the voltage up, and another one steps it back down near your base.

Laying them is easy: hold the cable, sweep your gaze, the line follows — around corners and up stairs. The thin cables are laid voxel by voxel, along a wall, under a shelf, as neat as you like. Right-click a cable with an empty hand: its sheet shows what it carries and how much is used.

Switches, relays, logic gates: real logic

This is where tinkerers have fun. A light switch cuts or lets the power through. A button lets it through for a second and sends a signal on its signal cable. That signal is a number from 0 to 255, and the devices listen to it:

• A lamp wired to a signal cable only lights while the signal is there.
• An electric relay closes a power line when its command passes halfway.
• A transistor lets through a share of the current that follows the signal: a dimmer, a speed control.
• A valve opens a pipe on command, a door or a trapdoor opens when the signal rises and falls shut when it drops.
• Optical fibres carry signals very far, and an octo fibre carries eight channels at once, each in its own colour.
• Since alpha 1.0.9, logic components — a delay, a logic gate (AND, OR, NOT, and now NAND, NOR, XOR), an op-amp, a memory, an optical coupler — and a display panel that shows live values turn it into real electronics: a blinking clock, a counter, the battery's charge in percent. All of it is in our logic gates guide.

Sensors and automatic doors

Sensors turn the world into signals. The presence sensor watches the space in front of it: a player or a creature comes close, it sends 255 and holds it a few seconds after they leave. Wire it to a door: you have an automatic door. To a lamp: a porch light. The level sensor reads how full a tank is: wire it to a valve or a pump and your tank never overflows. The chunk sensor tells you when the land around it is loaded and settled.

And to see what your signals do, there's the signal writer: a chart recorder that draws your signal on paper, sheet after sheet. Take a chart, right-click: the graph opens on a paper card. Perfect for checking when your panels produced, or how often the door opened in the night.

1. 1

   Power

   A generator or a panel with a battery, and a small power cable to your entrance.

2. 2

   The sensor

   Place a presence sensor facing the path, and feed it with the cable: it needs a little power to watch.

3. 3

   The command

   Run a signal cable from the sensor to your door. Walk up: it opens. Walk in: it falls shut behind you.

Radio: across the planet, to the Moon

Antennas carry signals without any cable. There are 256 channels: an antenna that receives on the channel of an emitter puts what it hears on its own signal cables. Press a button at home, a lamp lights up on the other side of the valley.

Two kinds of antennas. The omnidirectional mast talks all around, perfect for a village. The dish concentrates its beam in a narrow cone: aimed, it carries much farther for the same power. You aim it through a spyglass view, or you tell it to follow the Moon (or, from the Moon, the Earth): it turns on its own as the planet spins. The farther you want to reach, the more power it asks — the Moon costs a lot. And the Earth and the Moon block the waves: when the Moon sinks below your horizon, the link is cut until it rises again.

Power and signals: two separate things

Here, signals and power are two separate things. Logic runs on thin signal cables, while real power flows in power cables and has to be produced, carried and paid for. Optical fibres (up to 10 km) and radio carry signals very far, to the Moon, and ready-made logic gates, delays and memory come with their settings engraved on them. Power also drives the rest of your base: motors turning shafts, booster pumps pushing pipelines, the Furnace smelting aluminium and lithium, the gas plant splitting water into hydrogen and oxygen — the propellants of real rockets — and filling dewars with them. A fuelling tower on the launch pad pours the dewars into your rocket.

Still being reworked

Electricity and radio arrived in October 2026 and were reworked during the alpha into a second, cleaner version: ports on every device, transformers, relays, transistors and sensors, logic components, port names when you hold a cable, and settings engraved on the models (an antenna's "CH 7"). The ideas above are the stable ones. Exact numbers — how many watts a panel gives, how far a mast carries — may still change, and each device's in-game sheet always shows the current values.

Built something that hums? Show it to your friends: play together on Mac, PC and Linux, and light up your street with lamps and decorations.